AbstractGround calcium carbonate (GCC) was modified by starch with the aid of sodium stearate and sodium hexametaphosphate. The GCC was encapsulated within the complex. The effect of the dosages of sodium stearate and sodium hexametaphosphate on the coating weight of modified GCC and the complex utilization rate were studied. The SEM images of modified GCC were compared with that of unmodified GCC. The results showed that the dosage of these two modifiers affected the coating weight of modified GCC and the complex utilization rate.